1, She's as slippery as an eel.

2, He's as slippery as an eel - you can never get a straight answer out of him.

3, They may be wise as an owl,(http://sentencedict.com/slippery as an eel.html) slippery as an eel or even a snake in the grass.

4, Beware of that peddler, for he is slippery as an eel.

5, The man can't be trusted. He is as slippery as an eel.

6, He is as slippery as an eel and simply refuses to be pinned down on anything.

7, The man the police want to talk to is slippery as an eel, and has so far escaped arrest.

8, The man they wanted was a New Zealand-born heroin tsar, sought in a dozen countries but slippery as an eel.

9, I advise you not to do business with him - he's as slippery as an eel.

10, Nobody could catch the wet ball, it was as slippery as an eel.